I. Field of the Invention
This invention relates to the field of lawn mowers, in more particularly to the air induction system of the mower hood of a riding lawn mower.
II. Description of the Related Art
It is well known in the art to provide ventilation in the hood of a riding lawn mower in order to cool the engine. Also, the air pulled in through the hood is used in mixing oxygen with the gasoline to create combustible conditions to provide power in the engine. However, most of the prior art mowers have the ventilation slits in the top of the mower hood. This allows rain and other debris to enter the mower engine, causing problems of rust and dampness.
One type of riding lawn mower is disclosed in U.S. Pat. No. 4,969,533 to Holm et al. Holm discloses a tractor including a dual screen filtering arrangement located upstream of a radiator and an engine combustion air inlet. Although the Holm patent discloses the use of air inlets on the side of the mower hood, it does not disclose the creation of air induction cavities solely by connecting an upper hood and a lower hood. The present invention also does away with the need for screens to prevent debris from entering the engine.
One type of riding lawn mower is disclosed in U.S. Pat. No. 5,782,312 to Murakawa. Murakawa discloses slits formed in a front surface of a panel body on the left and right sides for drawing in engine cooling air. These slits are provided particularly to guide the cooling air forwardly and downwardly. In the current invention however the slit for drawing in the air is aligned along the side of the mower hood, as opposed to the panel body near the steering wheel as in Murakawa. The length of the air induction cavity in the current invention also allows a good volume of air to be drawn into the engine. The Murakawa patent also does not disclose any method for separating the hot and cold air underneath the hood, and does not have the inventive blower housing as described in the current invention. The current invention therefore provides advantages over the cooling capabilities of the Murakawa invention.
Another riding mower is disclosed in U.S. Pat. No. 5,113,819 to Murakawa et al. Murakawa discloses air guide covers that, together with the surface of the engine body, define a cooling air passage that allows the oil cooler to be supplied with cooling air that has not been heated by the engine. However, this separation of the hot and cold air takes place within the engine, as opposed to underneath the hood, and separate from the engine as in the current invention. The current invention also draws the air into the engine through air induction cavities that are located lower than the air intake, thereby preventing debris from entering the engine.
Another riding lawn mower is described in U.S. Pat. No. 5,207,187 to Kurohara et al. Kurohara discloses two shield members connected to opposite ends of each other and extending downwardly between the sidewalls of the engine and the side surface of the hood respectively. This shield allows the cooling air to be introduced from the rear of the engine and to flow along opposite sides of the engine to reach an air suction opening above the engine. However, these shield members do not separate the hot and the cold air from going into the engine, and also the air drawn in, in Kurohara, comes from the back of the mower hood or the front of the panel body underneath the steering column.
The present invention contemplates a new and improved air induction system, which is simple in design, effective in use, and overcomes the foregoing difficulties and others while providing better and more advantageous overall results.